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Can you hear me? Thank you. Hello. Hey, sorry, I just thought I double check. Do you want to flick through? Yeah, I'll flick through them. Um, yeah. Can you see all the slides? Ok, so you can, so you can just see the slides and me. Is that right? Ok, cool. Um I can't, I can't see who's actually in the. No worries. Yeah. Ok. That's ok. Otherwise we can, we can start in about five minutes or so. Ok, cool. Thank you. Bye bye. All right guys. Um, we'll just go five minutes, uh, just to give you the chance to join and we can get going. I haven't presented a med before, but I hope it's ok and you can see all my slides. I hope. Great. Thank you for putting in the chart. All right guys, I think we can get going. Um, can let other people join as and when so. Um, hello everyone. My name is Rishi and welcome to the first orthopedics revision session run by Visa and I'm currently act one in plastic surgery. Uh, but I've got an interest in pursuing orthopedics. Um, so today we'll be covering a range of topics including septic arthritis, open fractures, compartment syndrome and bone tumors. So I hope you find these sessions useful. Um Please do interrupt me uh or put something in the chat um at any point throughout the presentation. So this week, um it's a basic introduction. Um And in the coming days, we'll be covering upper limb and lower limb and I'll be completing a series with a plastic surgery talk as well. So the session today should last around 45 minutes to an hour. So, um, let's get going. So we're gonna begin with a question. Um So a 32 year old lady presents with an acutely swollen tendon knee joint, she's in severe pain and on examination, the knee is red, swollen and warm. She's unable to wait there. The F one on call suspects a diagnosis of septic arthritis. So, what's the mainstay of diagnosis for clinically suspected cases of septic arthritis? Is it a plain film radiograph? An MRI scan, a joint aspiration, an arthroscopy or a blood culture? So, if you wanna just put your uh answers in the chats and then we can go through them. Perfect. So we've got a few number threes and that's the right answer. So, joint aspiration is um the mainstay of diagnosis and for all joint aspirations performed for septic arthritis, it's really important that this uh joint fluid is sent for a gram stain. Um A leukocyte count, um polarizing microscopy to check for things like gout and pseudogout and also a fluid culture. So this allows antibiotic therapy to be um could be tailored um to the specific organism and other investigations such as an X ray will be able to identify early signs of infection such as periosteal reactions. But if we're suspecting something like an Osteomyelitis, an MRI scan is um the gold standard investigation. So, arthroscopy is quite an invasive procedure and it's typically done in theater. So this is not something that uh would be done in the emergency department. Say. So let's go on to talk about septic arthritis. So it refers to any sort of infection of a joint and it requires a high index of suspicion, suspicion in a patient presenting with an acutely tender, hot swollen joint. So it can affect both native and prosthetic joints and the main causative organism is typically staph aureus. We need to consider streptococcus gonorrhea and finally, salmonella particularly in those with sickle cell disease and this can be an exam question. So, in any young patient presenting with a single, acutely swollen joint, you should always think of gonococcal septic arthritis until you can prove that otherwise. So, gonorrhea is an infection. It's pretty common and delaying treatment puts the joint at significant danger and in your exams or in your finals, it might say that the gram stain revealed a gram negative diplococcus and the patient may have urinary or genital symptoms. And this might trick you into thinking that um the patient has reactive arthritis. But remember that it's important to always exclude go gonococcal septic arthritis first, as this is the more serious condition. So, spread of septic arthritis is either via bacteremia. Um a direct inoculation or spread from, you know, adjacent osteomyelitis and septic arthritis can cause irreversible articular cartilage damage and this can lead to severe osteoarthritis later on. So the main risk factors for osteoarthritis. So, um so for uh septic arthritis, not osteoarthritis, so it's age over 80 preexisting joint disease such as rheumatoid arthritis, diabetes, renal failure, hip or knee joint prosthesis and IV drug use. So, the clinical features. So patients will most commonly present with a single swollen joint causing severe pain and fever will be present in probably around 50% of individuals, but it's absence should not rule out aseptic arthritis. So, on examination, the joint will appear red, swollen and warm and there will be pain on active and passive movements and a joint effusion may also be present. So usually the joint is pretty rigid and the patient will not be able to tolerate any sort of passive movement and they'll be unable to weight bear. And the symptoms are more obvious in a native joint infection, um rather than a prosthetic joint infection, um in which the the features can be a bit more subtle. So, um as I said, as septic arthritis should be the main differential diagnosis in anyone presenting with a single, painful, swollen joint. But it is possible to consider other differential diagnoses. And this in this includes sort of a flare of osteoarthritis, a hemarthrosis. So, blood within the joint, um uh, crystal arthropathies such as gout and pseudogout, um, rheumatoid arthritis and other inflammatory arthropathies, erective arthritis and lyme disease. So this is infection from the spread of um, bite of a tick. So, moving on to investigations. So routine bloods including a full blood count and ACR P should be sent and this should be sent alongside urate levels to check for things like gout. Blood culture should also uh be sent um especially in those uh with evidence of sepsis. And a joint aspiration is essential and should be also performed before antibiotics are given if this is safe to do so for those involving a prosthetic joint, joint aspiration should only be done in theater. So it's important that cultures and joint ace are sent where possible prior to starting antibiotics in order to tailor um treatment to that specific organism and to avoid things like antibiotic resistance. And an X ray of the affected joint is often performed and in its early stages, no evidence of any sort of disease may be present. But as the sort of um disease progresses, um y there may be signs of um soft tissue swelling or joint space widening. So other imaging performed is pretty rarely performed and an ultrasound can be done in order to guide joint aspiration and for drainage, particularly of the hip because it's quite a deep joint. Um And CT MRI scanning is a very sensitive method to assess joint damage. And it's typically used if there's any sort of uncertainty around the diagnosis. So CT and MRI can also be used in um specific joint infections just to sort of assess the extension of the disease into um the media and all this, for example. And um the image on the right. So you can, it's, it's a synovial fluid analysis. And in septic arthritis, you can see that um the color will be pretty turbid and or cloudy in appearance, there'll be a really high white cell count and a really high neutrophil count. So, moving on to management of septic arthritis and IV, antibiotic treatment should be started after any sort of planned cultures and aspirates have been performed and antibiotics are usually long term antibiotics, often 4 to 6 weeks initially. IV. And then after about two weeks, these can do oral therapy. So different trusts are different guidelines and um if you guys are already f ones or F twos or so at medical school, um every trust as I said will have their own guideline, which you, which you should follow. So if the infection is within the prostatic joint, um a washout is typically needed um and sometimes revision surgery as well. So there septic arthritis under arthroscopy and it can be visualized as sort of an irregularity of the articular cartilage and there will be a bit of bone debris within the joint space as well. And the complications of septic arthritis include um, osteoarthritis later on in life, osteomyelitis and the spread of infection to other bones and obviously sepsis. So, this brings us to an end and to septic arthritis, part of the, of the talk and uh, we'll go on to another question. So a year old lady presents with a contaminated open ankle fracture. The wound is more than 10 centimeters and high energy with inadequate soft tissue coverage. So the first part of the question, which of the following immunization status is required to know in this case, is it yellow fever, tetanus diphtheria or meningitis if you wanna put your answers in the chat and then we can go through. Ok, great. So we got a couple of number two. So tetanus. So yeah, all patients with any sort of open fracture with both an early antibiotic cover and an up to date tetanus vaccination. So, part B um which classification system is most commonly used for open fractures? Is it the Anderson classification? The Salter Harris Garden classification or Powells classification? Good. So you've got a couple of number ones there, Guilla Anderson classification. We'll go into a bit more detail about this later on. Uh just to go through the other answers. So, Salter Harris is a method used to grade fractures that occur in Children and those that involve the growth plates. A golden classification is um sort of a system to uh categorize like a feur fractures. And Powells classification is based on the vertical orientation of the fracture line in the femoral neck fractures. I wouldn't worry too much about Powells fra uh Powell's classification at all. Um I mean, I've rarely come across it as well, but Salter Harris and Garden classifications can come up in new sounds as well. So, open fractures. So a fracture is open when there is any sort of direct communication between the fracture site and the outer environment and this is most often through the skin. Um but pelvic fractures can be internally open so the fracture can penetrate through the vagina or the uh for example, um a fracture can also become opened by either an into out injury uh where the sharp bony ends penetrate through the skin from beneath or an out to in injury where there is a high energy injury resulting in direct blow to the skin, causing significant trauma to the skin, soft tissue muscles and bone. So whilst any sort of fracture can become open, the most common fractures are at the tibial fracture, phal forearm, ankle and metacarpal fractures. And the outcomes of an open fracture can be considered in sort of uh the following way. So extensive skin loss. So this can range from very small wound to significant tissue loss. Um where plastic surgery may have to get involved, um the extent of soft rate. So this can also range from very little soft tissue injury to significant muscle tendon ligament loss. Um the neurovascular status and neurovascular injury. So, nerves and vessels may also be compressed due to limb deformity and sort of go into a bit of an arterial spasm and sometimes uh neurovascular injury is severe enough to require an amputation and finally infection. So the rate of infection is often very high following an open fracture due to direct contamination. Um and essentially systemic compromise and infection can also be introduced in theater following the need for insertion of metal work in order to stabilize the fracture. So let's go on to um the castilla Anderson class classification. Um And so the three, so type one is typically a lesser one centimeter wound um that is clean, type two, the wound is between 1 to 10 centimeters and again clean, type three, more than 10 centimeters, but with adequate soft tissue coverage, type three B, more than 10 centimeters without adequate soft tissue coverage and type three C. Uh all injuries with any sort of vascular injury and sort of um a pretty like simple way of um remembering how you can manage these sort of fractures is that a three A fracture can typically be managed by orthopedics alone. Three B will require plastic surgery input to cover the soft tissue loss. And type three C will require vascular input say he wants investigations and management and another question. So a 55 year old man is hit by a forklift truck and sustains an open fracture of his forearm. He's an extreme pain ale. So which of the following is the most appropriate initial treatment. It's an opiate analgesia, fluid resuscitation, airway assessment, cross match of four units or IV antibiotics. So if you wanna put your answer in the chart, OK. So we've got a three and we've got a number one. OK, good. So the answer is airway assessment. So never forget your at assessment in the management of any sort of acutely unwell patient or patient presenting with acute trauma. So it's really important in sys and um if you have an interest in surgery in MRC S part BO as well, open every sort of answer with, I would like to approach this patient using a cat approach following a TLS guidelines and then you score form. So um essentially the management of open fractures um can be considered in the following way. So all patients will require antibiotic cover. And as I said, an up to date tetanus vaccination, a plain film radiograph will be required following suitable resuscitation, urgent realignment and splinting of that limb is also required. Definitive surgical management requires debridement um of the wounds and the fracture sites, removing all sort of dead tissue. And this should happen either immediately if it is contaminated or within 12 to 24 hours in non contaminated wounds. You should also ensure that the wound is thoroughly washed out in Ed with normal saline. And based on the gel Anderson classification, your eyes need orthopedic input, plastic surgery, input and all vascular inputs. Um If soft tissue coverage is required, this should typically occur uh within 72 hours. But if there's any sort of vascular compromise, this has to happen as soon as possible, typically within six hours. Ok. So that brings us to an end um open fractures. Um We'll move on to another question. So a 28 year old male presents with severe pain in his forearm, disproportionate to the injury sustained. He had a fractured, he's fractured his radius which subsequent sling and analgesia is not relieving the pain. The F one un call suspected diagnosis of compartment syndrome. So, what's the normal pressure found within the fascial compartment? Is it 0 to 8 millimeters of mercury? 15 to 2530 to 45 or 50 to 60? Ok. Ok. So we've got um 15 and we've got number one as well. So the answer is actually number one. So normal pressure within the compartment is always between zero and eight millimeters of mercury and anything higher is a high risk of pre, well, it present a high risk of compartment syndrome. And the main thing to remember when you're considering a diagnosis of compartment syndrome is paying out of proportion to the level of injury sustained and the pain is often so severe that um analgesia is not usually effective. And if you see a pain patient with disproportionate pain. After an injury in your exams, the diagnosis is most probably uh compartment syndrome. So, compartment syndrome um is essentially defined as any sort of um pressure increase within a confined compartmental space and any fashion compartment can be affected. But the most common include the leg, the thigh, forearm, foot, hand and the buttock. It typically occurs following high energy trauma, um crush injuries or fractures that result in vascular injury and other causes that you need to be aware of include type casts or splints and also a DVT. And um the image on the right just highlights the muscles of the posterior compartment of the forearm. So moving on to the pathophysiology. So fascial compartments involve muscles, nerves and blood vessels surrounded by a fascia. And a fascia is essentially uh a fibrous connective tissue that um encases the the contents of that compartment. It's totally not able to stretch or expand. And so any sort of fluid deposit within the fascia can cause an increase in the intracompartmental pressure. So as the pressure increases the veins will be compressed, this increases the hydrostatic pressure within them, causing fluid to move out of the vein veins and into the compartments. And this can also again increase the intracompartmental pressure. After the veins are compressed, the nerves are then compressed. And this because this can cause sensory or motor deficits. Um So, paresthesia is a pretty common sys um symptom. And finally, as the intracom compartmental pressure reaches the diastolic pressure arterial inflow will be compromised. And this can lead to ischemia. So typical cool um pulselessness, paralyzed limb, and this is a late of missed compartment syndrome. So, symptoms tend to present within a few hours but they can develop up to 48 hours after the injury. And the as I said, the most reliable symptom of compartment syndrome is severe pain disproportionate to the level of injury, sustained and pain that doesn't respond to analgesia. So the pain is typically made worse by passive stretching of uh that compartment and paresthesia is typically a a common feature and the compartment itself may feel tense um but not too swollen as the the fascial compartment, as I said, is very tight and rigid and it doesn't allow it to uh to distend. So, if the disease progresses and compartment syndrome is ultimately missed, um the features of of acute arterial insufficiency will develop. These are often referred to as sort of five ps. Um So pain pallor personally called paralysis and pulselessness. So investigations. So the diagnosis of compartment syndrome is typically clinical based on the symptoms. Um but the clinician should also have a high degree of suspicion for compartment syndrome in post operative patients. Um The most reliable diagnostic test is an intracompartmental pressure reading and it should not increase um exceed um eight millimeters of mercury. So, here's another question. So um what biochemical test is key in the diagnosis of rhabdomyolysis which can occur secondary to compartment syndrome. Is it C RP white cell count, uh Creatin carna ddimer test or corrected calcium. Yeah. So pretty easy question, Chris in car. So um typically the re incar level will be five times after the limit of normal and it's usually in thousands, if not tens of thousands in compartment syndrome. So management. So, decompressive fasciotomy is um the definitive management for compartment syndrome and this should be done within six hours uh of suspected compartment syndrome. So, fasciotomy essentially involves cutting through the fascia. So all compartments should be decompressed. Um So typically in the leg, it involves an anterolateral incision uh to decompress the anterior and lateral compartments and a posterior incision to, to decompress both the superficial and deep posterior compartments. Um The compartment is then explored. Um The underlying fascia is debrided and uh that any necrotic tissue is again debrided, the wound is typically left open um and covered just with a simple dressing. Um And if, if the swelling improves it can be um stitched up and, and closed directly. But often plastic surgery will have to be involved um in order for a potential skin graft. So this brings us to end of compartment syndrome. Um And uh we'll move on to another question. So all four are the following typical radiological features of osteoarthritis. Apart from which one? Yeah. Have you got any answers? So, um Great. Yeah, it's an easy question. So, increased joint space. So in osteoarthritis, there is a reduction of joint space along with subchondral sclerosis, subchondral cysts and osteophyte formation. And this image shows pretty severe osteoarthritis of the right hip. So, moving on to um, so the pathogenesis of osteoarthritis. So it's typically known as the wear and tear disease. Um And it involves the degradation of the cartilage and subsequent remodeling of um the bone due to first of all, an active response of the chondrocytes. Um and in within the articular cartilage and the inflammatory cells in the surrounding tissues. So, there'll be a release of enzymes from these cells and these break down collagen destroying the articular cartilage. So, once the articular cartilage has been destroyed, the underlying bone will be exposed and this bone can undergo sclerosis and subsequent remodeling that results in the formation of osteophytes and subchondral bone cysts, joint space is typically um lost over time and osteoarthritis has many different uh causes and these can be primary, so no obvious cause or secondary due to trauma or um any sort of connective tissue disease. The main risk factors include um, obesity, age, um being f being female and manual labor occupations. So, the most common joints affected are the small joints of the hands and feet. Um And osteoarthritis also affects the hip and knee joints as well as the cervical spine. So, clinical features. So, typically patients will present with symptoms that are pretty chronic and, um, they tend to worsen over time. And these features include pain stiffness in the joint. And, um, the stiffness is sort of worsened by activity and relieved by rest and the pain tends to worsen throughout the day. Um, whereas the stiffness can sometimes improve prolonged osteoarthritis can result in deformity and a reduced range of movement. And um the typical deformity that may come up in your exam um are swellings of the P IP Js, um which are known as Bouchard nose and also swellings of the distal interphalangeal joints. The PR PJ known as the Heberden's nodes and an easy way of remembering this is by the outer hebrides. So, Heberden's nodes are distal, you may also sometimes get fixed flexion deformity. Um as you can see in the image um at the top of the screen. So the the leg will be held in a fixed flexion deformity. So, investigations, so typically nice suggests that osteoarthritis can be diagnosed without any sort of investigation. If the patient is over the age of 45 they have typical pain associated with activity and they have no morning stiffness. Um and the classical radiological features of osteoarthritis, as I'm sure you all know can be remembered um using the acronym loss. So loss of joint space, osteophyte formation, subchondral cysts and subchondral sclerosis. So, moving on to the management. Um And it's typically a stepwise uh ladder to the management of osteoarthritis. And it typically follows the, the the who analgesic ladder. So, first of all, as with any sort of question, um in terms of how would you manage pain in this patient, you should always start with conservative measurements. So the patient should be educated about their condition and the patient should be, they should be emphasized the importance of muscle strengthening and exercise. And patients who are overweight should also be um advised on weight loss. And some um non pharmacological interventions include physiotherapy, um local heat or ice packs. And as I said, um it's essentially a stepwise approach to the use of analgesia. So first of all, simple paracetamol and topical nonsteroidals, then if this doesn't work, you can add in an oral um NSAID um typically with a proton pump inhibitor in order to protect against gastric ulcers. Um and then you can consider opiates such as codeine and morphine. But you should use these cautiously as they can cause significant side effects. And some of these serious side effects include a withdrawal. Um intraarticular steroid injections can also be used and can be used to provide temporary reduction in that inflammation and can improve symptoms. And finally, um the last step of the ladder is a joint replacement and this should only be used or considered in severe cases. And the hip and knee joints are the most commonly replaced joints. Um So this brings us to end of osteoarthritis. Um And uh we're gonna move on to the final section of um the presentation uh, bone tumors. So, this is a bit more of a complex section. Um And we'll start off with another question. So, a 12 year old male presents with localized constant pain and a tender soft tissue mass on the proximal tibia. The pain is not relieved by nsaids and an X ray shows medullary and cortical bone destruction with sunburst pattern. So, what type of bone tumor is this uh person presenting with? Is it a ewing sarcoma? An osteosarcoma, a chondrosarcoma, osteo osteoid osteoma or a chondroma. I know they all sound the same, but we'll go on to try and differentiate all of these in the coming slides. Ok. Ok. Good. Ok. So we've got a few number twos and that's the right answer. Ok. So osteosarcoma and osteo osteosarcoma, osteosarcomas are the most common primary malignant bone tumor and they tend to affect either Children or those over the age of 65. And they're most commonly found at the metaphysis of distal femur or proximal tibia radiologically that would typically be that sunburst pattern. Um And we'll go into more detail on the different types of bone tumors uh in the next few slides. Ok. So, bone tumors. So, um a bit of a heavy topic, but it can be divided into first of all primary and secondary malignant or sort of metastatic tumors. So, primary tumors arise from cells which constitute bone and can be divided into, again benign and malignant types. Metastatic bone tumors make up the most of the disease burden. And primary bone tumors are actually only accountable for about 1% of bone tumors in the UK. So, in Children and adolescents, bone cancer is more common. Um and this table sort of outlines the various different types of benign and malignant bone tumors. So, metastatic spread from other cancers is by far the most common cause of any sort of bone cancer. And the most common primary sites include um the kidney, uh thyroid, lung, prostate and breast. Um and the most common site for any sort of bony metastasis is the spine. And in order to remember sort of the red flag symptoms in back pain, you can use the, the Acron tuna fish. So T stands for trauma. U is unexplained weight loss and is neurological symptoms a age over the age over 50 f is the presence of fever. I um if they have a history of IV drug use, s steroid use and H is a history of cancer. So these are just the red flag symptoms of back pain, which you should sort of raise your eyebrows to. Um. So, metastatic disease is rarely treated surgically. And unfortunately, many of these patients are just treated palliatively. Um sometimes prophylactic nailing of certain long bones can be performed. Um if there's a high risk of any sort of pathological fracture occurring from that metastatic disease. And um nailing can typically be performed in the femur or the humerus. And the scan on the right shows uh sclerotic bone metastases secondary to metastatic bone cancer, metastatic prostate cancer rather. So, the risk factors and the clinical features. So the risk factors for essentially developing uh a primary bone cancer um are three fold. So, first of all, there may be a genetic association. So, mutations within the RB one and P 53 gene are associated with an increased risk of osteosarcomas. Um mutations within um TSC one and two. So, those uh which are responsible for tuberous sclerosis are associated with an increased risk of chondromas particularly during childhood. Other risk factors include previous exposure to radiation or chemotherapy. Um and other benign uh bone conditions such as pagets disease and fibrous dysplasia can also increase the risk of osteo sarcoma. So, the main symptoms um in bone cancer is pain and this is typically not associated with movement and the pain is often worse at night and as the tumor becomes bigger, sometimes you can feel a mass. Um and if the patient presents with a fracture without any history of trauma. So, this is known as a pathological fracture. A bone tumor needs to be suspected. So we'll start off with benign bone tumors and first of all osteoid osteomas. So these arise from osteoblasts and often occur around the age of 10 to 20 years. They're more, they're more common in males and they're usually pretty small tumors, so less than two centimeters and they're located around the metastasis of long bones such as the proximal femur or the tibia. And they sort of present with localized progressive pain that's worse at night and typically made better with nonsteroidals. Um There may be associated swelling, tenderness or limping and radiologically, it will typically be a small mass comprised of a radiolucent nardus with a a rim of reactive bone. And the radiolucent images appeared dark, whereas radioopaque images appeared light. So the suspicion of um these types of bone tumors need to be confirmed on an MRI scan. And most of these tumors are managed conservatively with serial x rays done every 4 to 6 months. Um But in those with severe pain, surgical resection may be required. They have a really good prognosis and most of these tumors just resolve spontaneously. So, another benign bone tumor is an osteochondroma and these form as an outgrowth from the metastasis of long long bones. And they're covered with a sort of cartilaginous cap. And again, they develop between at the ages of 10 and 20 they're more common in males. Most of these osteochondromas, they're, they're found incident incidentally and they can be asymptomatic and slow growing, but they can cause occasional deformities or compression on nerves if they grow large enough. And as you can see on the X ray. Um it's typically you can see these bony outgrowths from the metastasis pointing away from the joint. Um And you can see this affecting the knee joints in this, in this x-ray. So, osteochondromas again can be managed conservatively with serial x rays um every 4 to 6 months. Um but as with osteoid osteomas, um surgical resection may be required if there is any significant deformity or neurological symptoms are present. Ok. So chondromas, so chondromas arise from chondroblasts. Um These are within the medulla of the bones or near the cortical surface of the bones. They typically present between the age of 2050 they most commonly affect the, the long bones, the hands, the femur and the humerus, most are asymptomatic, but they can present a as a pathological fracture. And on X ray, they appear as a well circumscribed oval lucency with an intact cortex. And most of these chondromas are asymptomatic but large or symptomatic chondromas may require removal and subsequent bone grafting. And there's a small risk of trans trans transformation from a chondroma to a chondrosarcoma which is malignant. So, giant cell tumors arise from the multinucleated giant cells and they occur in patients aged between 2030 they affect the epiphysis of long bones and patients again will typically present with pain, swelling or limitation of joint movement. And on X ray, you'll typically uh see this soap bubble appearance and this is something that can come up in your exams. Um So you can see it essentially a soap bubble appearance located here in the distal radius on the X ray on the right. And surgical resection is typically required for these giant cell tumors as they can cause significant reduction in mobility. So, um resection followed by bone grafting. So this covers benign bone tumors and we'll move on to malignant bone tumors. So, as I said, osteosarcomas are the most common malignant primary bone tumor. And um they have a sort of bimodal age of onset. So, between the age of 10 to 14 or later on in life and those over the age of 65 and these are most commonly seen in patients with pagets disease. Um So, osteosarcomas are mostly found at the metastasis of the distal femur or the proximal tibia. And patients who will present with localized constant pain and a tender soft tissue mass, which may be palpable. An X ray will show um medullary and cortical bone destruction and a sunburst pattern. And a periosteal reaction is essentially the formation of knee bone in response to injury. And a tissue biopsy is required for diagnosis. And osteosarcomas um usually require aggressive surgical resection with subsequent um adjuvant chemotherapy and osteosarcomas have a high tendency of metastases to the lung or other bones as well. So, ewing sarcomas. So these are pediatric malignancies and they're more common in males and they typically affect the diaphysis of long bones. So, these patients typically present with a painful and enlarging mass with tenderness um around the joint as well. It is often mistakenly uh initially mistaken for osteomyelitis. But an X ray will demonstrate these lytic lesions um and these periosteal reactions producing layers of reactive bone um leading it to the characteristic um onion skin appearance on, on X ray. So, management is typically um in the form of chemotherapy followed by uh surgical excision. Um and um the condition can be associated with um genetic translocation diseases of chromosomes 11 and 22. So, chondrosarcomas and these are malignant tumors of the cartilage. Um And as I said, they can transform from benign chondroma. So in the mean age of onset is between the age of 4060. Uh they typically affect the pelvis, shoulder and the ribs. Um And on X ray, uh you'll typically see multiple large lytic lesions with calcification and remodeling. An excision is the main form of treatment. And prognosis typically depends on the grade and location of the tumor. So I guess in general determining type of T on X ray can be difficult but to make it easy for exam purposes, benign lesions are often pretty sharp and well defined and they lack any sort of um soft tissue involvement and there's no sort of cortical destruction, either malignant lesions. Um they're usually poorly defined, they have rough borders and they involve soft tissues and most benign tumors can be managed with observation serial x rays every 4 to 6 months. But for, for malignant tumors, surgical resection is typically the mainstay for any sort of malignant tumor. And so this brings us to the end of uh bone tumors and we'll end the, the, the talk with one final question. Um just highlights the importance of anatomy. So a 44 year old male injured his right arm in a road traffic accident. And several months later, he complains that he cannot flex his arm properly and outside of his arm is numb. On examination, there's wa wasting and weakness of the flexor muscles of the upper arm and loss of sensation on the lateral aspect of the forearm. So which nerve is most likely to be involved? Is it the C four nerve root? C six nerve root, the muscular cutaneous nerve, posterior interosseous nerve so called the suprascapular nerve? Sure. OK. So we've got ac four. Um again, another C four. OK. So we've got quite a few ones. Um So the answer is actually the number three. So the musculocutaneous nerve. So the musculocutaneous nerve affects um nerve roots C five to C seven and particularly dermatomes C five to C seven. And the musculocutaneous nerve is responsible for elbow flexion and supination as well. And its sensory functions are of the lateral aspect of the forearm as most commonly injured in brachial plexus injuries. So, the posterior interosseous nerve um is a deep branch of the radial nerve and uh acts as a supinator and the suprascapular nerve innervates the supraspinatus and the infraspinatus muscles. So, these muscles form part of the rotator cuff muscles. Great. So, um this brings us to the end of um the first presentation. Um I hope you found it useful. Um I'm happy to take any questions if you want to put them in the chat or um I'm pretty sure you'll get a recording of this session as well as the slides if you want. Um, yeah, and before I forget it would be really helpful. Um, if you could please fill out a, um, feedback sheet for me. Um, feedback, I'm sure is the bane of your lives, particularly if you're at university. But it would be really be really be helpful for me. I think, um, we'll send it over to you in due course. No problem at all. Thanks guys for, for joining. Ok, great. So, I think, um, the feedback link has been put in the chart. So just before you go, um, if you could fill it out, that would be great. And don't forget, in a couple of days time, I'll be doing an upper limb talk as well. And then, um, also a lower limb to, uh, where I cover the spine. And then finally, um, as I'm currently on an eight month plastic surgery rotation, I'll be doing a plastic surgery talk because, um, I know it's not really covered during med school but it is a pretty cool specialty. Hi, Lilian. Um, what do you mean by catch up? Um, I think, I think the, the talks will definitely be recorded. Um. Oh, ok. Your connection went bad. Yeah. So don't worry, all the, all the talks are recorded. So if you wanna just flick through, um, the questions, um, or just target your revision to a particular part of the presentation, I'm sure you'll be able to do that as well. All right guys, does anyone have any last minute questions? Otherwise we can, uh, we can end the, we can end the talk there? All right guys, I'll, um, I'll close the video now. Have a nice evening, everyone.